The principle of USB camera is to convert the light signal light into image data signal. Therefore, the complicated natural environment such as strong light, backlight and weak light will immediately improve the imaging quality of USB camera.
The image quality of USB camera will immediately affect the actual effect and feeling of face recognition and face detection. Therefore, when the terminal equipment manufacturer selects the USB camera model, it should also pay attention to the key imaging components and important main parameters of the USB camera, so as to ensure that the image quality previously collected meets the requirements of the terminal equipment manufacturer.
Among the three key components of the USB camera module: lens, image sensor and DSP image, the lens is responsible for capturing objects and focusing captured images on the image sensor. Its basic parameters include field angle, focal length, CRA, distortion, glare, etc. USB camera module generally adopts a fixed focus lens with faster focusing speed, stable imaging quality and accurate metering.
For the image sensor that converts optical signals into analog signals for output, its basic parameters include sensor size, reasonable definition, specifications, etc. it is strongly recommended that CMOS sensors with the characteristics of high processing speed, small function loss, faster speed, low cost, etc. Then, the color image data signal is transferred to the DSP image CPU of the terminal device after it is improved. The high-quality DSP can improve the original integrated IC wide dynamic range by more than 30%.
